With the advent of videocassette recorders (VCRs), TV viewers are able to record TV program events that are broadcasted in a given time slot and playback the recorded program content later. During the recording, a VCR changes the electrical signals of a program content into magnetic signals and stores the magnetic signals on magnetic tape. When playing back, the VCR changes magnetic signals into electrical signals and the attached TV set displays the program content of the signals on its screen.
With the development of digital technology, the VCRs are being superseded by digital video recorders (DVRs). Like a VCR, the functionality of a DVR is to record broadcasted program events for later playback. During recording, a DVR changes the electrical signals of broadcast program content into digital information, such as MPEG data streams, and stores the digital information in a memory device or directly stores the pre-digitized TV signals in the memory. When playing back, the DVR converts the digital information back to analog signals. An attached TV set displays the program content of the signals on its screen.
To record TV program events using a VCR, a user must manually select a channel and control the VCR or have someone else perform the operation. By using a DVR, however, the user may establish a program recording sequence by programming the DVR according to a TV program guide and have the recording performed automatically.
Although the DVR enables users to specify the recording time, channel, and duration for a plurality of events, it cannot meet the increasing needs in defining and capturing the program events in a more intelligent way. For instance, in situations where a user is far away from his DVR and TV set, he will be unable to program his DVR and record the program events that he likes.
What is desired is to establish a communication system through which a user may access to a centralized TV program guide database and program his DVR anywhere.
Additionally, such a system would provide a user with the ability to transfer recorded program material from one DVR to another DVR, or a server to a DVR, in a secure manner that preserves the program material provider's copyrights.